MEDICAL AND SURGICAL COMPLICATIONS IN PREGNANCY
| PLACENTA PREVIA AND ACCRETA— Maurice L. Druzin, MD, Charles B. and Ann L. Johnson Professor, Chief, Division
of Maternal-Fetal Medicine, Associate Dean for Academic Affairs, Stanford University School of Medicine, Stanford,
CA
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| Definitions and epidemiology: placenta previa—presence of placental tissue overlying internal cervical os; bleeding
main complication; complete placenta previa—placenta completely covers internal os; central placenta previa—
internal os equidistant from anterior and posterior placental edges; 20% to 30% of previas central; partial previa—
placental edge partially covers internal cervical os; marginal previa—placenta proximate to internal os; low lying
previa—not true previa; placenta somewhere near lower uterine segment; used to describe placental edge lying within 2
to 3 cm of internal os; associated with increased risk for bleeding; incidence—≈4 per 1000 pregnancies >20 wk gestation;
risk factors—increasing parity, maternal age, and number of prior cesarean deliveries; 10% after 4 cesarean deliveries;
high likelihood of accreta with anterior placenta previa
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| Clinical presentation: painless vaginal bleeding; 10% to 20% of patients present with uterine contractions; management
of bleeding previa often depends on whether patient having true uterine contractions; initial bleeding episode often
occurs around 34 wk of gestation; about one third occur <30 wk of gestation; bleeding likely to occur during third trimester
because of development of lower uterine segment and increasing uterine contractions; changes in cervix and lower
uterine segment apply shearing forces at placental attachment site, resulting in placental detachment and bleeding;
abruptio placenta—not bleeding placenta previa; different etiology
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| Diagnosis: associated conditions—malpresentation, premature rupture of membranes (PROM); no correlation with any
specific anomaly; bleeding—placenta previa should be suspected in any pregnant woman >24 wk of gestation presenting
with bleeding; absence of abdominal pain and uterine contractions distinguishing feature between placenta previa and
abruptio placenta; some women with placenta previa have uterine contractions in addition to bleeding; bleeding placenta
previa with contractions indication for tocolytics; imaging studies—diagnosis must be determined by ultrasonography
(US); transabdominal US diagnostically accurate; overdistended bladder can compress lower uterine segment and give
appearance of anterior placenta previa; have patient empty bladder and re-scan; high diagnostic accuracy with transvaginal
US (gold standard in many institutions); probe does not need to come into contact with cervix to provide clear image,
but exercise caution; transabdominal and transvaginal US useful as complementary diagnostic studies; translabial US alternative
technique; persistence after second-trimester diagnosis—significant number of patients have placenta previa
that converts to normal location at delivery; avoid placing patient on bed rest; perform follow-up scan; longer placenta
previa persists, more likely present at delivery; at 15 to 19 wk, risk for persistence 10% to 12%; much higher risk in third
trimester until delivery; complete previa more likely to persist than incomplete previa; amount of overlap of placenta on
cervix correlates with probability of persistence of previa at delivery (>40% risk if >25 mm, and 20% if <15 mm)
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| Placenta accreta: life-threatening disease requiring early diagnosis; US findings suggesting accreta—hyperechoic
boundary lost and placenta appears continuous with bladder wall; intraplacental sonolucent spaces may be observed adjacent
to involved uterine wall; diagnostic modalities—transabdominal color Doppler strongly recommended; magnetic
resonance imaging (MRI) recommended if accreta suspected; transvaginal US often accurate
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| Management of patient with placenta previa: avoidance of coitus; avoid performing digital cervical examination;
instruct patient to seek immediate medical attention with vaginal bleeding; woman with active vaginal bleeding should be
admitted to hospital’s labor and delivery unit for maternal and fetal monitoring; although controversial, speaker believes
tocolytic therapy should be considered for all patients admitted with vaginal bleeding; individualize management; cesarean
delivery route of choice; speaker believes vaginal delivery not worth risk for obstetric hemorrhage even if mother hemodynamically
stable; conservative management treatment of choice for stable patient <34 wk gestation; Stanford
University Medical Center protocol for patient with bleeding placenta previa 24 to 37 wk—admit to labor and delivery
unit, tocolysis prn, continuous electronic fetal monitoring, laboratory studies, early consult with oncology surgeon
and interventional radiologist, steroids, bed rest, and regular diet; consider outpatient management if patient hemodynamically
stable, has reassuring fetal status, lives within close proximity to hospital, and has available transport
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| Delivery: amniocentesis performed at 36 wk; counsel patient about possibility of hysterectomy and obtain informed consent;
schedule cesarean delivery during days and hours when hospital fully staffed and consultants readily available;
suite; consider employing interventional radiologist and surgical consults
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| Closing remarks: velamentous umbilical cord—associated with anterior placenta previa; look for cord and establish
where coming from; PROM—tocolytic therapy reasonable; placenta accreta—major complication profuse life-threatening
hemorrhage; hysterectomy treatment of choice; placenta percreta—high mortality and morbidity; case reports of
methotrexate used with placental accreta, but not recommended; treatment of choice planned delivery and planned hysterectomy;
employ senior gynecologic surgeons and most experienced health care providers; Skupski et al concluded attention
to improving hospital systems necessary for care of women at risk for major obstetric hemorrhage important in
effort to decrease maternal mortality from hemorrhage
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| SURGICAL COMPLICATIONS IN PREGNANCY —James G. Quirk, MD, Professor and Chairman, Department of Obstetrics,
Gynecology, and Reproductive Medicine, State University of New York at Stonybrook
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| Introduction: 1% to 2% of pregnancies complicated by nonobstetric surgical problem; adnexal mass indication for most
surgical interventions; appendectomy undertaken in ≈1 in 1000 pregnancies; biliary tract disease results in surgery in ≈1
in 2000 pregnancies; clearly indicated diagnostic procedures and therapeutic interventions should be undertaken during
pregnancy; adverse perinatal outcomes do not appear to be increased in face of uncomplicated surgery and anesthesia
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| Challenges: proper approaches to disease management and prudent decisions about need for surgery pose challenges to
obstetrician and surgeon; normal physiologic changes of pregnancy may increase maternal risk or alter management;
special concerns—potential fetal risks for teratogenicity of anesthetics and diagnostic imaging; alterations in uterine
blood flow may affect fetus as consequence of anesthesia and patient’s placement on operating table; risk for preterm labor
and delivery associated with undergoing laparotomy; pregnancy may result in delay in diagnosis, causing increased
maternal morbidity and mortality; potential conflict between needs of mother and best interest of fetus exists; in most
cases, what is best for mother is best for fetus
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| Study data looking at fetal outcome of nonobstetric surgery during pregnancy: large-population study
concluded that fetal outcomes consequence of disease, not surgery; case-controlled study looking at 20,000 women delivering
babies with congenital anomalies confirmed lack of association between first trimester surgery and congenital anomalies;
study involving 78 gravidae undergoing surgery showed preterm delivery occurred more frequently than in cohort of
matched patients; timing of surgery greatest risk for preterm labor (25% in third trimester, ≈8.5% in second trimester);
proximity of operative site also increased risk for preterm labor (highest rates associated with adnexal surgery, followed by
appendectomy and cholecystectomy); no increase in perinatal mortality; speaker’s conclusions—delay in diagnosis due
to pregnancy with visceral perforation and peritonitis one of greatest surgical dangers to fetus; ruptured appendicitis may
lead to 100% fetal wastage; 50% negative appendectomy rate considered acceptable, given morbidity associated with disease
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| Teratogenicity of irradiation: etiology of birth defects unknown in majority of cases; drug and chemical exposure
believed to constitute 3% of risk; embryogenesis occurs between 8 and 9 wk of gestation (central nervous system continues
to develop beyond that time frame); only small percentage of exposed embryos manifest effect of teratogen
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 | General anesthesia: considered safe based on findings of several studies; Kallen and Mazze suggest possible small increased
risk for neural tube defects if surgery performed in window of 5 to 7 wk of amenorrhea (3 to 5 wk after fertilization)
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| Perinatal exposure to ionizing radiation: data show no evidence of mental retardation or microcephaly if exposure occurred
<8 wk of gestation or >25 wk of gestation; highest risk in individuals receiving 12 rad at 8 to 15 wk of gestation
and individuals receiving 21 rad at 16 to 25 wk of gestation; no evidence of any increased risk with exposure ≤5 rad;
American College of Obstetricians and Gynecologists (ACOG)—exposure ≤5 rad not associated with increase in
fetal anomalies or pregnancy loss; American College of Radiology—no single diagnostic procedure results in radiation
dose that threatens well-being of developing embryo and fetus; National Council on Radiation Protection—
fetal risk considered negligible at ≤5 rad when compared with other risks of pregnancy, and risk for malformations significantly
increased above control levels only at doses >15 rad
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| Adnexa: 1 in 200 pregnancies complicated by adnexal mass >6 cm; variable among studies, but perhaps 1 in 6 adnexal
masses require surgery; majority cystic teratomas; ovarian torsion—most common and serious sequela with benign
lesion; incidence 5%; rupture most common secondary complication in first trimester
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| Management protocol: first trimester—manage expectantly; operate if mass persistent and large; second trimester—
if malignancy suspected (high index of suspicion), operate; manage expectantly with low index of suspicion for malignancy;
third trimester—wait for delivery before operating, unless high index of suspicion for malignancy
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| Appendicitis: numerous differential diagnoses; diagnosis difficult in pregnancy because appendix displaced, uterus enlarged,
and laboratory values distorted; fever and tachycardia may not be part of presentation; Parkland Hospital
study—direct abdominal tenderness rarely absent; rebound tenderness frequently not present; rectal tenderness frequently
absent after first trimester; anorexia present in only one third to two thirds of patients; presence of white blood
cells in high number in urinalysis in absence of bacteria useful in reinforcing diagnosis of appendicitis; mortality of appendicitis
complicating pregnancy is mortality of delay; use lower threshold for surgery (consequences of delay
severe)—negative appendectomy rate 25% to 35% acceptable; delay in surgery >24 hr after presentation associated with
marked increase in rate of perforation; perforation occurs twice as often in third trimester as it does in first or second trimester;
fetal mortality—associated with nonperforated appendicitis 3% to 5%, perforated appendicitis 20% to 30%; fever
and dehydration can cause preterm uterine contractions, so keep patient well hydrated and treat with antipyretics and
antibiotics; maternal mortality— 0.1% with unperforated appendicitis, 4% with perforated appendicitis; make incision
at point of maximum tenderness; make midline incision with diffuse peritonitis; minimize amount of uterine manipulation;
ensure operating table tilted; use of external fetal heart rate monitoring controversial; summary—appendectomy
complicates ≈0.5% of pregnancies; physical examination may be ambiguous; US may be helpful (spiral computed tomography
[CT] used in speaker’s institution); obtain surgical consultation early; general anesthesia acceptable; no difference
in morbidity or mortality with laparoscopy compared to laparotomy; extended fetal monitoring necessary
postoperatively (speaker prefers tocodynamometer); ambulate patient as soon as possible postoperatively
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| Biliary tract disease: complicates ≈25 per 1000 pregnancies; most common cause cholecystitis secondary to cholelithiasis;
increased frequency of biliary colic and cholecystitis in pregnant women compared to aged-matched controls; increased
bile viscosity, increased micelles, and increased risk for gallstone formation; asymptomatic in 2.5% to 10% of
pregnant patients; speaker opines no reason to intervene for presence of gallstone; intervention recommended with recurrent
biliary colic before patient develops cholecystitis; medical management of cholecystitis—no solid consensus; meperidine
(Demerol) or morphine for pain, intravenous fluids, nasogastric suction, and low-fat diet; surgical intervention
before third trimester recommended with recurrent or refractory case
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| Breast disease: any suspicious breast mass found during pregnancy should prompt aggressive plan to determine cause,
whether by fine-needle aspiration or open biopsy; surgical treatment should not be delayed; in absence of metastatic disease,
wide excision, modified radical mastectomy, or total mastectomy with axillary node staging can be performed; fetal
risks from these procedures minimal, and incidence of abortion negligible
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| Laparoscopy vs laparotomy: data show laparoscopy safe, especially <20 wk of gestation; prevalence of low birth
weight, preterm labor, and fetal growth restriction same for laparoscopy and laparotomy; advantages of laparoscopy—
early mobilization, rapid postoperative recovery, and early return to normal activities beneficial in preventing deep
venous thrombosis (DVT; provided surgeon equally skilled with laparoscopy as with laparotomy); early return of gastrointestinal
activity due to less manipulation of bowel may result in fewer adhesions and less bowel obstruction; low rate
of fetal depression due to decreased pain and narcotic use; disadvantages—technical difficulty because of gravid uterus,
possible injury to uterus, and potential decrease in uteroplacental blood flow because of increased intra-abdominal pressure
(can compromise uteroplacental perfusion); pneumoperitoneum pressures should be minimized (8 to 12 mm Hg) and
not allowed to exceed 15 mm Hg
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Educational Objectives
| The goal of this program is to educate the listener about maternal complications in pregnancy. After hearing and assimilating
this program, the clinician will be better able to:
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| 1. Describe the 4 types of placenta previa and describe the clinical presentation of a woman with a previa.
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| 2. Cite the most appropriate imaging studies for diagnosing placenta previa and summarize the management of a
patient with placenta previa and accreta.
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| 3. Sunnarize the management of a patient with placenta previa and accrete.
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| 4. Discuss the risks of general anesthesia and x-ray in pregnancy.
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| 5. Summarize the management of pregnant women requiring nonobstetric surgery.
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Discussed on This Program
Meperidine HCl [Demerol]
Morphine sulfate [Astramorph PF, Avinza, DepoDur, Duramorph, Infumorph, Infumorph 200, Infumorph 500,
Kadian, MSIR, MS Contin, Oramorph SR, RMS, Roxanol, Roxanol 100, Roxanol T]
Suggested Reading
Bhide, A et al: Recent advances in the management of placenta previa. Current Opin Obstet Gynecol 16(6):447,
2004; Carver TW et al: Appendectomy during early pregnancy: what is the preferred surgical approach? Am Surg
71(10):809, 2005; Cunningham FG et al: Appendicitis complicating pregnancy. Obstet Gynecol 45(4):415, 1975;
Horgan R: Placenta previa, placenta accreta, and vasa previa. Obstet Gynecol 108(3):693, 2006; Mazze RI et al:
Appendectomy during pregnancy: a Swedish registry study of 778 cases. Obstet Gynecol 77(6):835, 1991; Skupski
DW et al: Improving hospital systems for the care of women with major obstetric hemorrhage. Obstet Gynecol
107(5):977, 2006; Warshak CR et al: Accuracy of ultrasonography and magnetic resonance imaging in the diagnosis
of placenta accreta. Obstet Gynecol 108(3):573, 2006; Wing DA et al: Management of the symptomatic placenta
previa: a randomized, controlled trial of inpatient versus outpatient expectant management. Am J Obstet
Gynecol 175(4 Pt 1):806, 1996.
Faculty Disclosure
In adherence to ACCME guidelines, the Audio-Digest Foundation requests all lecturers to disclose any significant financial
relationship with the manufacturer or provider of any commercial product or service discussed. For this issue,
the faculty reported nothing to disclose.
Dr. Druzin was recorded at Antepartum & Intrapartum Management sponsored by the University of California, San
Francisco School of Medicine, held on June 8-10, 2006 in San Francisco, CA. Dr. Quirk was recorded at the 61st Obstetrical
and Gynecological Assembly of Southern California, sponsored by the Obstetrical and Gynecological Assembly
of Southern California, held on February 24-25, 2006 in Pasadena, CA. The Audio-Digest Foundation thanks
the speakers and the sponsors for their cooperation in the production of this program.
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